Factors Affecting Eye Witness Testimony Flashcards
What is an eye witness testimony
Refers to an account given by people of an event they have witnessed and is the evidence that is usually given in court
What are the 3 factors that affect the accuracy of EWT
.anxiety
.misleading info
.post event discussion
What is a leading question
It is a question phrased in such as way as to prompt a particular kind of answer
Who conducted the study for factors of EWT
Loftus and Palmer
What was the aim of Loftus and palmers experiment
It was to examine the effect of leading questions on the accuracy of EWT
What was the procedure of Loftus and Palmers experiment
45 american participants (students) watched film clips of car accidents and then have them questions to answer about the accident. The question was
‘About how fast were the cars going when they hit each other?’
What was the findings and conclusions of Loftus and palmers experiment
estimated speed was calculated:
○ Contacted: 31.8 mph
○ Smashed: 40.5 mph
● Leading questions had biased the eyewitness recall of an event.
● The verb ‘smashed’ suggested that the speed of the car was much faster than when the verb was ‘contacted’ and the ppts altered their responses accordingly
What were the 5 groups (5 verbs) that were usd
.hit
.smashed
.contacted
.bumped
.collided
What are the strengths of Loftus and Palmers investigation
there is real world application as there is application to their findings of the criminal justice system
What are the limitations of Loftus and Palmers study
.it lacks population validity as there is only 45 American students and so the study is both culturally biased and is also biased upon age
.they didn’t tell their participants the true aim of their search and so it went against the BPS code of ethics
.they also used artificial materials and so it may tell us little about how leading questions actually affect EWT
what is post event discussion
when there is more than one witness to an event. Witnesses may talk about what they have seen with co-witnesses - or simply hear what they have experienced
Why could memories be contaminated
If there is a discussion about an event between witnesses then it could lead to memory contamination
What is an example of compliance and internalisation
Witnesses tend to go along with each other to either win social approval or if they believe witnesses are right or wrong
Who did the research for post event discussion
Gabert ET AL.
What was the aim for Gaberts study
To see if post event discussion had a possible impact on peoples EWT
What was the procedure of Gaberts study
Participant’s were paired together. They were given the same video (a crime) however the video each ppts watched was from a different point of view to the other.
○ Ppts could see elements in the event the other could not.
● They then discussed with each other what they had seen on the video before they both completed a recall test.
What were Gaberts findings
● 71% mistakenly recalled aspects of the event that they did not see in the video but had picked up in the post event discussion with the other participant.
● There was a control group (no post event discussion)
○ 0% errors made.
What is the limitation of Gaberts study
It has questionable ecological validity and so these results do not reflect everyday examples of crime, where witnesses are exposed to less information
What is a strength of Gaberts study
She tested 2 different populations (uni students and older adults) and found little difference. Therefore her results provide good population validity and allows us to conclude that post-event discussion affects younger and older adults in a similar way.
What is the 3rd factors affecting EWT
Anxiety
What was the conclusion that was reached about EWT after 30 years of research
30 years of research. Suggested that EWT is unreliable
Who is Wells
They are a researcher who studied 40 people who were convicted and then release later after a result of DNA evidence
What was found from the 40 people that Wells studied
That more than 90% of those obviated were wrongly convicted based on the basis of EWT
What is the general effect of anxiety on EWT
There r both negative and positive effects so there is no general effect
What is the weapon focus effect
Where the witnesses main focus is on the weapon being used in the crime and this causes a state of anxiety which leads to other details in the situation being overlooked and neglected
What is anxiety
Anxiety is an unpleasant emotional state where we fear that something bad is about to happen
Who studied anxiety for EWT
Johnson and Scott
What was the aim for Johnson’s and Scott’s study
To investigate the effect of a weapon on EWT accuracy
What wa the hypothesis of Johnsons and Scott’s study
That heighten anxiety would increase the accuracy of EWT
What was the procedure
They led ppts to believe they were going to take part in a lab study and were made to wait in a waiting room.Whilst sitting in the waiting room the ppts heard an argument in the next room. There were 2 conditions: low anxiety and high anxiety conditions
What was the low anxiety condition
Low-anxiety condition: A man walked through the waiting area, carrying a pen with
grease on his hands.
What was the high anxiety condition
High-anxiety condition: ppts heard a heated argument, this was accompanied by the sound of breaking glass. A man walked out of the room, holding a paper knife that was covered in blood.
What were the findings and conclusion
● 49% of the ppts who had seen the man carrying a pen were able to identify him.
● This was compared to 33% of ppts who had seen the man carrying the paper knife.
● Tunnel theory of memory
What is the tunnel theory of memory
It argues that witness’s attentions narrows to focus on a weapon, because it is a source of danger and anxiety. Supporting the weapon focus explanation
What are the 2 issues with John and Scotts
Deception and that it was carried out in a lab
Explain deception as an issue
The participants were led to believe that they were sitting in the waiting room waiting for the experiment to begin, when in fact that was part of the real experiment. However this was needed in order for thee to be no demand characteristics despite it being an ethical issues
How was the deception dealt with
They told the participants that they can withdraw at the end if they wanted to if they don’t want it published
What was the issue with the study being conducted in a lab
This could lead to demand characteristics which would affect the validity as we may not know if there was actually a relationship with anxiety
What were the studies that contradicted Johnson and Scotts findings
Yuille and Cutshalls, Riniolo
What did Yuile and Cutshall and Riniolo study
That anxiety has a positive effect on EWT
What wa the procedure for Y&C
It was during a real life shooting where the shop owner shot a theirs dead. There were 21 witnesses, 13 agreed to take part in the study.Interviews were held 4-5 months.These were compared with the original police interviews made at the time of the crime.The witnesses were asked to rate how stressed they had felt at the time of the incident, using a seven point scale.
What were the findings for Y&C study
Witnesses were very accurate in their accounts and there was little change in the amount or accuracy after 5 months. Some details were less accurate.
Those ppts who reported the highest levels of stress were most accurate (88% compared to 75% for the less stressed group)
What are the strengths of Y&C
Creating anxiety has ethical issues due to psychological harm so with this study it already happened so there is no need to create it hence why it is better due to less ethical issues
